Carbohydrates
Carbohydrates are a primary source of energy (4 calories per gram), found in most foods, especially in the form of sugar in today's junk food carbohydrate diet.
Carbohydrates are converted by the body into glucose, which is then stored in your muscles and liver. The glucose is converted to glycogen for storage within the specific muscle, which will lock the glycogen within the muscle. Muscle fatigue takes place when the glycogen within the specific muscles becomes depleted, its important to know that the glycogen stored within an individual muscle can not be used for another muscle.
Because glycogen stored in your muscles, can not be released back into your blood stream as glucose, your liver will break down its glycogen stores into glucose, enabling your blood stream to transport the glucose to the working muscles.
- 75% of glycogen is stored in the muscles - around 400 grams.
- 25% of glycogen is stored in the liver - around 100 grams.
Its important to remember that all excess CHO will be stored by the body, not as glucose or glycogen, but as FAT, this is why a lot of people on low fat diets still continue to put on weight, they consume excess calories from CHO not fats.
Glycogen is stored in your muscles and liver, with approximately 2 - 3 times its own weight of water, in order to help the chemical breakdown of energy and heat produced. For persons who decide to go on a CHO reduced diet, such as the Atkins Diet, they will obliviously lose a lot of weight in the first few days, unfortunately this weight is what the body will require to function properly, water and glycogen. Losing these valuable reserves will prevent the body working at an optimum level, especially any form of exercise or mental concentration, as the brain relies on its energy source of glucose from the blood stream.
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FUEL RESERVES IN A PERSON WEIGHING 70 KG
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| Potential energy available (kcal) | Glycogen | Fats | Proteins |
| Liver | 400 | 450 | 400 |
| Adipose tissue FAT | 0 | 135,000 | 0 |
| Muscle | 1,200 | 350 | 24,000 |
Your CHO intake will vary dependent upon your demands, you may be expending a high amount of calories in your lifestyle (work) or simple through your exercise.
Aim to get around 50 - 60% of your calories from natural unrefined sources of complex CHO. Your body will break down CHO into glycogen far quicker after exercise, so aim to refuel within 2 hours of finishing your workout.
Eating small regular meals throughout the day, will help keep your blood sugar levels at an optimum level, especially if they contain good sources of complex CHO, rather than sugary based foods, which will give you an instant high, followed by a depression.
Avoid taken large meals with high CHO content late at night, or eating large meals close to your sleep time, especially if you're concerned about your body fat levels, your body will only be able to store some of the CHO in your muscles and liver, the rest is converted and stored as fat.
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CALCULATING CHO REQUIREMENTS
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| Activity Level | Grams CHO / KG /Day |
| Light < less than 1 hour per day. |
4- 5
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| Light / Moderate - 1 hour per day. |
5 - 6
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| Moderate - 1 or 2 hours per day. |
6 - 7
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| Moderate / Heavy - 2 to 4 hours per day. |
7 - 8
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| Heavy > more than 4 hours per day. |
8 - 10
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Complex Carbohydrate's: -
Natural, raw, unrefined, or unprocessed carbohydrates are surrounded by other factors such as proteins, fats, vitamins, and minerals.
Carbohydrates in the natural form should be the only ones we consume in any quantity. All of these carbohydrates contain some fibre (cellulose) which is impossible to digest, thereby giving bulk to the foods we eat.
Good examples of these carbohydrates are:
- Potatoes, Whole grain bread, Brown rice, Wholemeal pasta, Fresh or frozen vegetables and Pulses.
- In the U.S. diabetes is fast becoming one of the countries biggest killers, due to the fast amounts of sugar laced in refined products.
- Sugar is an anti nutrient containing no vitamins and minerals, yet in order for the body to make use of sugar it needs B complex vitamins.
- Sugar is an irritant to the stomach and creates gastric acid contributing to heartburn and ulcers.
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Sugars can cause enlargement of the liver, kidney and adrenal glands as well as an increase in the production of insulin, estrogen and adrenal hormones.
Food Examples Containing Sugar's: -
- Cakes and biscuits: Fruit cake, Iced cakes, Jam Sponge, digestive.
- Drinks: Cola, Ribena, Orange juice, Drinking chocolate, Beer.
- Puddings: Fruit Yogurt, Crumbles, Fruit in syrup, Pastry's, Ice Cream.
- Spreads: Jams, Honey, Lemon curd.
- Breakfast cereals: Sugar coated cereals, Muesli.
- Soup: Tomato soup.
- Sweets: Most sweets like chocolate and wine gums.
- Sauces: Sweet pickle, Tomato ketchup, Chutney.
- Fruits and Vegetables: Bananas, Peas, Baked beans, Apples, Sweet corn.
During exercise, certainly over long periods 60 / 75 minutes plus, you should find that consuming CHO in the form of a banana or sports drink beneficial to your performance, always practice with any food intake in training, not just on your race day to make sure that your body becomes accustomed to the intake.
Its important to take regular vitamin and mineral supplements to help the body function optimally, especially vitamin B for those on a high CHO diet.
When looking at planning your meals, aim to get your CHO intake from good quality fibrous or starchy CHO:
Good sources of Fibrous CHO
All vegetables and salad foods, ideally ones in season that have been freshly picked and eaten either raw, or not over cooked, avoiding the use of salt or unnecessary oils in the form of salad dressings.
Good sources of Starchy CHO
Potatoes, ideally with their skins left on (also high in vitamin C)
Sweet Potatoes & Yams
Carrots
Grains such as Barley - Brown Rice - Oatmeal
Pulses such as Lentils - Peas - Beans (not canned baked beans)
Whole grain pasta's - cereals and bread.
Aim to avoid quick cook rice's, white pasta's and sugary oatmeal, checking your food labels for hidden sugar's in the form of sucrose, glucose, fructose, dextrose, lactose and the many hidden variations of sugar.
Good sources of simple CHO are those found in natural fruit (fructose), fruits that have been dried without sugar added are also good. Fruits that have been canned will generally have their skins removed and juices generally will be sweetened - also avoid excessive amounts of pure fruit juice as the fructose (sugar) content will be high, always mix 50 - 50 with water.
Along with knowing the good sources of CHO, its also important to remember that there are so bad and also ugly variations which should be used in limitation or not at all.
Bad CHO, are those that have generally been put through the processing mill, basically to make them taste sweeter or easier to cook and digest. These foods will generally make up the bulk of most people's diets, however its only a small change to convert the bad to good - most of the good products will be in the same location as the bad, generally on the lower shelf's, not at eye level.
White rice - white bread - sweetened cereal's (non whole grain). It's easy to change the bread and rice you use, sweeten your cereal's with fructose in the form of fresh fruit.
Ugly CHO should be avoided as these are the ones that are full of junk sugar, and though they may be low in fat, they are still high in calories - remember if your body can't store your CHO in the muscles and liver, it will store it as fat.
The list for ugly CHO is huge, basically simple, its simple sugary foods such as sweets - cakes - bleached breads or white flour baked goods. A huge mistake that a number of people make is the consumption of poor CHO in their fluid intake - canned drinks are full of sugar, just like most cordials, alcohol contains a high content of calories (7 per gram) with the sugars labeled as (mannitol, sorbitol, xylitol, lactitol, isomalt, maltitol) - you don't need to drink too many cans of beer to consume over 1,000 calories.